The use of water as a dispersing liquid for particle size analysis can often result in misleading or even incorrect data due to the presence of air bubbles that may be present in solution. If the air bubbles are not removed, the particle size analyzer may see them, and they may be incorrectly reported in the measured distribution. To solve this problem, Micromeritics has developed the AquaPrep. The AquaPrep operates by recirculating water through a hydrophobic capsule consisting of many thin-walled capillaries. A vacuum pump in turn provides suction on the outside of the capillaries. This results in a diffusion of dissolved air from the water through the capillary walls and into the vacuum pump. The air removed from the water is exhausted through a small tube at the front of the instrument. The AquaPrep is convenient, relatively small in size, and very simple to use. It is now available for the Micromeritics Saturn DigiSizer 5200 laser particle sizing system.